I recently acquired a N900. I tried to install Debian directly on the internal memory (I don't have an SD card) following this tutorial -> n900.elektranox.org/installation.html. But now, the phone no more boot up, nor appear via dmesg when connecting it via USB.
I've been reading that topic, and after trying many solutions on my computer, I think that's the best solution I have in order to revive my N900.
If there is someone like explit, who can help me by flashing it with F-Bus/Mbus Cable (Contacts under the battery) and UFS/HWK Flasher-Box, living in France, that would be awesome. If not, I could travel to Berlin to solve that issue.